The symptoms of narcosis may be caused by other factors during a dive: ear problems causing disorientation or nausea; early signs of oxygen toxicity causing visual disturbances; or hypothermia causing rapid breathing and shivering. Nevertheless, the presence of any of these symptoms should imply narcosis.
What's a Coronarita? It's a margarita with an upside-down Corona sticking out of it. Does it taste any good? You be the judge!
But the real reason has nothing to do with any of these. Here is the real reason: Two bartenders had a bet around a lemon wedge floating or sinking in beer. They saw a bottle of corona at hand, tested it out... rest is history.